They were originally loved flesh and blood, but in the end they turned against each other. If you fall in love with the same person, you are destined to lose it. The war to conquer the demons thousands of years ago, followed by the curse of the God of Creation, the Wind Clan and the Saint Clan met each other at war. Tragedy resulted. However, love finally resolves everything, and what is lost is the ultimate possession. In the vast world, they are as ethereal as mayflies, but they change their own destiny. They, the mayfly twins...